best scope for the ASI178MC

[myk68]

Hi,

I got myself the ASI178MC as a planetary imager with the possibility for Messier imaging due to the resolution/sensor size.  This was in the hope I could get some high res close images to show the details.

I have paired it up with a Mak 127 and currently have to say it doesn't seem to performing as I had hoped.

Am I asking too much of the scope/camera?   is there a better scope that I could match it to for this sort of imaging.?  I have a C8 that I could try but weight on the mount then starts to become an issue. 

Alternatively is it just that I haven't found the sweet spot yet and this set up should produce some good images.?

 

Thanks for looking

Mike

[newbie alert]

Are you disappointed as a planetary image or a messier one?

Solar system imaging relies on conditions ,if the Jetstream sits ontop of us then no equipment  will produce the goods

When you say you could use it with a C8 but then weight could become a issue on the mount, which mount is it?  

Some cameras can do both long exposure and very fast FPS but on the whole most can do one or the other ..

[myk68]

Hi Newbie

I haven't had chance to try for planetary yet but the same scope with a ASI120 did well.  This is more for Messier,  should have been clearer.

The mount is a HEQ5 pro but I also have cross bar with 80ED, Moonlite focuser, ASI533, guide scope and ASI120 on.  It might be ok but thought id ask about the ASI178 with a Mak127 first to see if there were any best combo's

Mike

[happy-kat]

Might be a fun combination to try capturing many shorter exposures on bright small targets or galaxies. Give it a go say using sharpcap live stacking.

[CCD-Freak]

I have used my ASI-178MM with a 6" f2.8 Hyper Newt (420 mm FL) with good result.   Single 180 second image.

I would think a scope of around 400 mm to 700mm FL would be a good choice for many objects using the 178 camera. 

Edited July 11, 2022 by CCD-Freak

[ollypenrice]

You need to go back to basics in order not to flounder around  in a sea of confusion.

Basics, in deep sky imaging, begins with image scale in arcseconds per pixel.  In other words, what area of sky lands on each pixel? Too much sky per pixel means low resolution of detail. Too little sky per pixel means not enough light per pixel. The atmospheric seeing (stability of incoming beams) imposes its own limit and the accuracy of your guiding may worsen that limit but cannot improve it.

Let's start with your shortest focal length, the ED80 DS Pro. With the ASI178 this focal length is already far too long.  It images at 0.83 arcseconds per pixel. You have no hope whatever, in long exposure imaging, of resolving detail at that scale. The atmospheric seeing will not allow it. That's with a non-negotiable full stop., alas.  It would be realistic to double it, meaning that your focal length should be half that of the  ED80, something around 300mm. Beyond that, you are in the realm of imaginary resolution, sometimes called 'empty resolution.'  Your target gets bigger on the chip but has no more detail than a smaller version of the same, but your field of view is pointlessly reduced.

Your camera's tiny 2.4 micron pixels would be brilliant with a camera lens. (Samyang 135?)

Why does it work as a planetary camera at long focal length? Because you take hundreds of ultra short exposures, a small number of which 'beat the seeing' by good luck - and you select and combine these. Once your exposure times go up to even a few seconds, let alone minutes, you can no longer beat the seeing.

In deep sky imaging you must match pixel size with focal length. (Some very advanced deep sky imagers are experimenting with fast frame deep sky techniques but this is not beginner territory.)

Olly